2012/08/02 by A. V. Volkov, Anton V. Volkov, A. A. Shylau +2
Materials Science · Physics and Astronomy · #Graphene research and applications #Magnetic properties of thin films #Quantum and electron transport phenomena #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.86.155440
published as Phys. Rev. B 86, 155440 (2012) · 7 pages, 6 figures
arxiv created 2012/08/02 · openalex publication_date 2012/10/22 · arxiv updated 2014/02/12 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We study the effect of electron interaction on the spin splitting and the g factor in graphene in a perpendicular magnetic field using the Hartree and the Hubbard approximations within the Thomas-Fermi model. We found that the effective g factor is enhanced in comparison to its free-electron value g=2 and oscillates as a function of the filling factor \ensuremathν in the range 2\ensuremath≤g*\ensuremath\lesssim4 reaching maxima at \ensuremathν=4N=0,\ifmmode±\else\textpm\fi4,\ifmmode±\else\textpm\fi8,... and minima at \ensuremathν=4(N+(1)/(2))=\ifmmode±\else\textpm\fi2,\ifmmode±\else\textpm\fi6,\ifmmode±\else\textpm\fi10,..., with N being the Landau level index. We outline the role of charged impurities in the substrate, which are shown to suppress the oscillations of the g* factor. This effect becomes especially pronounced with the increase of the impurity concentration, when the effective g factor becomes independent of the filling factor, reaching a value of g*\ensuremath≈2.3. A relation to the recent experiment is discussed.